package ltd.jdsoft.cute.bank.util;

public class LuhnUtil {

  /**
   * 匹配Luhn算法：可用于检测银行卡卡号
   * 
   * @param cardNo
   * @return
   */
  public static boolean matchLuhn(String cardNo) {
    int[] cardNoArr = new int[cardNo.length()];
    for (int i = 0; i < cardNo.length(); i++) {
      cardNoArr[i] = Integer.valueOf(String.valueOf(cardNo.charAt(i)));
    }
    for (int i = cardNoArr.length - 2; i >= 0; i -= 2) {
      cardNoArr[i] <<= 1;
      cardNoArr[i] = cardNoArr[i] / 10 + cardNoArr[i] % 10;
    }
    int sum = 0;
    for (int i = 0; i < cardNoArr.length; i++) {
      sum += cardNoArr[i];
    }
    return sum % 10 == 0;
  }
}
